Garbine Muguruza and Petra Kvitova both appeared to be in exceptional form in reaching the last-16 of the Charleston Open in the US.
Two-time Grand Slam winner Muguruza made light work of Poland’s Magdalena Frech, easing into the next round with a 6-1, 6-3 victory to earn a shot at 11th seed Yulia Putintseva.
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"I’m happy that I got this win, that I fought hard, that I kept my fighting spirit through the whole match, also in the second set which was tighter than the first set," Muguruza said after the match.
"I’m pleased with that, very simple."
She was followed on court by double Wimbledon champion Kvitova, who had a sterner test against Australian Storm Sanders, needing a tie-break to win the first set before wrapping up the second in routine fashion, taking it 6-2.
Coco Gauff, playing a round behind, was in demolition mode against former Wimbledon semi-finalist Tsvetana Pironkova, needing just 72 minutes to beat the Bulgarian 6-3, 6-0 to book her place in the round of 32.
Sloane Stephens picked up a 6-2, 6-4 win over Xinyu Wang, while Ons Jabeur, Anastasija Sevastova and Shelby Rogers also joined her in the second round.
World number one Ashleigh Barty begins her campaign later against Japan’s Misaki Doi in a packed schedule on day 5.
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